The United Nations treaty against torture gained additional teeth today with the entry into force of a mechanism that allows visits by independent international and national bodies to prisons and other places where people are deprived of liberty.

“This is truly a milestone in efforts to fight torture and impunity,” UN High Commissioner for Human Rights (OHCHR) Louise Arbour said of the new measure which is entering into force following its signature by 20 countries.

“I call on all other States to become party to the Convention against Torture and the Protocol. We have waited a long time for this treaty - let us now all work together to make it effective worldwide,” she added. “The monitoring mechanisms, both national and international, established in the Optional Protocol are critical new methods of ensuring the protection of detainees around the world against all forms of mistreatment.”

Secretary-General Kofi Annan has long called on all states to ratify both the Optional Protocol and the treaty itself, officially known as the Convention against Torture and Other Cruel, Inhuman or Degrading Treatment or Punishment.

The Protocol, adopted in December by the General Assembly, sets up an international Subcommittee on the Prevention of Torture with a mandate to visit places of detention in States parties. It also requires States parties to set up national preventive mechanisms with access to places of detention and prisoners held there.

Following these visits, the Sub-Committee and the national preventive mechanisms will make recommendations for improvements in the treatment and the conditions of persons deprived of their liberty, and work with relevant authorities to ensure the implementation of the recommendations.

Accession by Bolivia and Honduras on 23 May set the clock ticking for today’s entry into force. The other 18 States that have signed are: Albania, Argentina, Costa Rica, Croatia, Denmark, Georgia, Liberia, Maldives, Mali, Malta, Mauritius, Mexico, Paraguay, Poland, Spain, Sweden, United Kingdom and Uruguay.